Abrasive cut-off machines

ABSTRACT

An abrasive cutoff wheel operating at high speed to cut through a bar of hard metal or other material. The rotating wheel is moved into the work while a rocking, as well as a vibrating, motion is imparted thereto. Cooling fluid is circulated over top of the wheel and down to the area of cutting to dissipate the heat of friction, thence to a tank in the base of the machine.

United States Patent Inventor James L. Hensley.

Clinton, Tenn.

Appl. No. 736,779

Filed June 13, 1968 Patented July 20, 1971 Assignee The Carborundum Company Niagara Falls, NY.

ABRASIVE CUT-OFF MACHINES 19 Claims, 19 Drawing Figs.

U.S. Cl 5l/33 R, 51/266, 51/272 Int. Cl .1 1324b 7/00, B246 9/00, B24b 55/02 Field olSearch 51/33, 266,

[56] References Cited UNITED STATES PATENTS 1,952,334 3/1934 Robinson 51/33 3,245,176 4/1966 Muehling 51/33 2,855,733 10/1958 Allison l25/l3.| UX 1,734,002 10/1929 Belden 51/267 2,544,604 3/1951 Mader 51/272 X Primary Examiner-James L. Jones, Jr. Att0rneyKarl W. Brownell ABSTRACT: An abrasive cutoff wheel operating at high speed to cut through a bar of hard metal or other material. The rotating wheel is moved into the work while a rocking, as well as a vibrating, motion is imparted thereto. Cooling fluid is circulated over top of the wheel and down to the area of cutting to dissipate the heat of friction, thence to a tank in the base of the machine.

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ATTORNEY ABRASIVE CUT-OFF MACHINES SUMMARY AND DESCRIPTION .This Invention relates to improvements in Abrasive Cutoff Machines of the character used for cutting through blocks or bars of hard metal.

Hard metals, such as high-temperature alloys, have been difficult to cut with conventional-type saws. Producers of forgings have operatedbatteries of conventional saws in order to keep up with production requirements.

Attempts have been made heretofore to provide for the high-speed operation of abrasive cutoff wheels. An example thereof is illustrated by my prior U.S. Pat. No. 3,069,950, dated Dec. 25, 1962.

These abrasive cutoff wheels have advantages in service in the sawing of many structural shapes, such as bars, blocks and the like. Nevertheless, the operation thereof heretofore and particularly the speed of operation, has been limited due to the difficulty in adequately cooling the working surface. Another limitation is imposed by the nature of the cutting action produced by the saw on the work.

One object of this invention is to improve the construction of abrasive cutoff machines, particularly in the respects mentioned, and to overcome objections encountered in service while increasing the speed of operation of the machine.

Another object of the invention is to provide for more effective cooling of the cutoff wheel so as to allow operation of the wheel at high speed, in the order of 12,500 s.f.m. This speed of rotation provides a very high linear surface speed and yet the cooling action provided maintains the wheel at its cutting surface against deterioration and for effective operation.

Another object of the invention is to improve the cutting action of an abrasive cutoff wheel through the imparting of a compound motion thereto in its action on the work. This compound motion involves rotation of the wheel about an axis with the edge of the wheel bearing upon the work. During rotation of the wheel about said axis, either or both of two additional motions may be imparted thereto in contact with the work. One of these motions involves the mounting of the axis of rotation for swinging movement of the wheel bodily in an are so as to effect an arcuate cut on the work during rotation of the wheel in contact therewith. Another motion which may be applied to the wheel simultaneously with the aforesaid working movement is a vibration of relatively small amplitude. This bodily vibration of the cutting wheel which may occur simultaneously with the oscillating movement described, if these are used together, increases appreciably the speed at which the wheel can effect its cutting action on steel bars and shapes and the like.

These objects may be accomplished according to one embodiment of the invention by mounting the cutoff wheel on an arbor which is supported on the free end of a rocking frame to which swinging motion can be imparted by suitable power means and thus to shift the position of the wheel in its relation to the work. The arbor is supported on the rocking frame by being mounted on an auxiliary frame carried thereby and having means for imparting vibration to the auxiliary frame during operation of the wheel. This vibration is of relatively low amplitude so as to effect bodily shifting of the wheel back and forth in a path during the cutting action and which has been found to be very effective in increasing the speed of cutting action of the wheel on the work.

In order to provide for effective cooling of the wheel during high speed operation, a cooling liquid, such as-water, is circulated over the surface thereof. Water in sufficient volume and velocity is moved over the wheel by being circulated downwardly over the top thereof, escaping from the supply source by flowing downward on opposite sides of the wheel during this operation, thence into the water box provided at the bottom. The water box provides a settling tank and forming the base portion of the machine, it aids in stabilizing the machine.

This embodiment of the invention is illustrated in the accompanying drawings, in which:

FIG. 1 is a side elevation of the machine, taken at the feed side thereof;

. FIG. 2 is a similar view at the opposite side of the machine;

FIG. 3 is an end elevation, illustrating the machine at the front end;

FIG. 4 is a similar view at the rear end of the machine;

FIG. 5 is a detail side elevation illustrating the rocking frame for mounting the arbor;

FIG. 6 is a top plan view thereof;

FIG. 7 is a diagrammatic side elevation illustrating the water system in its relation to the wheel;

FIG. 8 is a top plan view of the water tank;

FIG. 9 is an end elevation thereof;

FIG. I0 is a side elevation thereof;

FIG. I1 is a detail cross section showing the springs of the vibrating frame, taken on the line 11-11 in FIG. 6;

FIG. I2 is a detail section on the line 12-12 in FIG. 7, showing the water control elements beside the wheel;

FIG. 13 is a detail side elevation ofthe material clamp;

FIG. 14 is a vertical section therethrough;

FIG. 15 is atop plan view thereof;

FIG. 16 is an end elevation of another water control segment;

FIG. 17 is a side elevation thereof;

FIG. 18 is a horizontal section through the guard structure on the line 18-18 in FIG. 2; and

FIG. 19 is a diagrammatic view, illustrating the cutting action of the wheel.

In the embodiment illustrated in the drawings, the machine includes a base 2 upon which is mounted a guard assembly 4 adjacent one lateral side of the base and upstanding therefrom. The guard assembly 4 has an opening 6 therethrough for the passage of the work W supported upon a roller conveyor, generally indicated at 8 and which conveyor is mounted on a support table 10 carried by the base 2. The conveyor extends along one end of the base, as shown in FIGS. 1 and 2. The table 10 also supports an upstanding fence 12 along one edge of the conveyor 8 as an abutment for the work W and against which fence the work can be held by a plurality of hydraulically actuated plungers, generally indicated at 14. One of these plungers is preferably located on each opposite side of the guard 4 so as to hold the work securely at the point of cutting action.

Clamping means is provided also for confining the work on the roller table 8. Such clamping means is preferably provided on each opposite side of the guard assembly 4. Each of these clamps is in the form of a plate 16 slidably mounted between guides 18. The lower edge of each plate 16 has fixed thereon a bearing plate 17 (FIGS. 13 to 15) adapted to bear upon the upper surface of the work. The clamping plate 16 is actuated by hydraulically operated plunger 20 connected with an ear 19 on the plate which raises and lowers the plate as desired. The plungers 20 on opposite sides of the guard assembly 4 are arranged in tandem and preferably are operated simultaneously in each opposite direction by means of suitable controls of the hydraulic system therefor.

Extending lengthwise of the base 2 are guide rails 22, shown in FIGS. 3 and 4. Mounted upon the rails 22 in guided relation therewith is a bed 24. Suitable antifriction means is provided between the bed 24 and the rails 22 to insure of smooth operation thereof in movement of the bed back and forth with respect to the base 2. This movement may be accomplished by suitable power means, such as a hydraulic cylinder 26 mounted on the base 2 between the rails 22, and operatively connected at one end with the base and at the opposite end with a depending abutment 28 fixed to the bed 24 for movement of the latter relative to the base, as illustrated in FIG. 3.

The bed 24 carries thereon in fixed relation to the bed upstanding journal boxes 30 (FIGS. 1, 5 and 6). The journal boxes 30 have a shaft 32 journaled therein. An auxiliary frame 34 is mounted on the shaft 32 for rocking movement with respect to the axis of the shaft. This rocking movement may be effected by power cylinders 36 (FIGS. 5 and 6). The body of each cylinder 36 extends between spaced side rails 38 of the oscillating frame 34 and is pivoted thereto on trunnions 40. The plunger of each cylinder 36 is shown as having a pivotal connection at 42 to a bracket 44 mounted in fixed position on the bed 24.

The rocking frame 34 has a pair of side rails 38 at each opposite side thereof projecting toward the front of the machine and which rails carry bearings 46 for journaling the oscillating frame 34 on the shaft 32. The pairs of rails 38 are spaced apart toward the forward end of the machine.

Mounted between the pairs of rails 38 is a vibrating frame 48 spaced at its lateral margins from the inner faces of the rails, as illustrated in FIG. 6. The vibrating frame 48 is pivotally supported on a shaft 50 journaled in bearings 52 supported by the respective pairs of side rails 38. Thus the vibrating frame 48 is free to swing or rock on the axis of the shaft 50 relative to the oscillating frame 34.

Mounted at one end ofthe oscillating frame 48 and secured thereto in a suitable or appropriate manner, as indicated at 54, is a housing 56 that extends transversely of the machine. The housing 56 hasjoumaled therein a saw arbor 58, on one end of which an abrasive cutoff wheel or saw 60 is mounted for operation by the arbor. The opposite end of the arbor 58 is provided with a pulley 61 (FIG. 1) connected through suitable belting 62 with a suitable power source for operation of the arbor. In this embodiment of the invention the power source is provided by an electric motor 64, the armature shaft of which has a pulley 66 receiving the belts 62 for driving the arbor.

The motor 64 is supported on the end of the oscillating frame 34 opposite the end where the arbor 58 is located. The base of the motor, indicated at 68, is seated upon a support plate 70 secured rigidly to the oscillating frame 34 and is capable of lengthwise sliding movement with respect thereto to tighten or loosen the belts 62. This adjustment of the position of the motor 64 may be accomplished by an adjusting screw 72 connected with the baseplate 68 of the motor. After such adjustment, the parts may be locked in adjusted position to maintain the proper tension on the belts by means of locking bolts 74. These bolts 74 extend through slots 75 in the plate 70 for relative adjustments between the plates 68 and 70, after which the locking of the bolts 74 holds the parts in place.

As shown in H6. 6, the arbor 58 is located on one side of the vibrating shaft 50. The vibrating frame 48 extends lengthwise of the oscillating frame 34 between the arms formed by the pairs of side rails 38. This vibrating frame 48 has upper and lower arm portions 76 overlapping respectively an intermediate rail 78 (FIG. 11) extending in bridging relation between the arms formed by the pairs of sideplates 38 and fixed to the latter. The rail 78, as shown in FIG. 11, is provided with a plurality of cushioning units 80 spaced lengthwise thereof, as shown in FIG. 6.

Each of the cushioning units 80 comprises a pair of coiled springs 82 disposed in bearing relation against opposite sides of the rail 78. An opening 84 extends through the rails 78, with countersunk portions 86 receiving the inner ends of the respective springs 82. The springs 82 are sleeved over guide pins 88, the inner ends of which extend into the opening 84. The outer end portions of the pins 88 are provided with heads 90, having screw threaded connections at 92 with the arm portions 76 of the vibrating frame 48. Shoulders 94 are provided at the inner ends of the heads 90 receiving thereagainst the outer ends of the springs 82 and forming adjustable abutments for the springs. The heads 90 may be adjusted through the screw threaded connections 92 by a suitable tool or wrench engaging sockets 96 formed in the outer ends of the heads. Plugs are shown at 98 closing the outer ends ofthe openings in the arm portions 76 and may be used if desired.

Seated upon the vibrating frame 48 is a power actuated vibrator 100 for rocking the frame about the shaft 50. Any suitable or desired form of vibrator may be used which will dissipate or cancel any lateral force and apply the vibrating force, either up or down, with respect to the vibrating frame 48. The vibration producedis of the desired pattern generated by the location of the pivot point 50.

The vibrator is mounted on the frame 48 and includes a pair of shafts rotating in opposite directions. These shafts carry weights fixed thereon so as to rotate with the shafts. The oppositely rotating weights oppose each other in the horizontal plane. One of the shafts is driven by a suitable variable speed motor, such as an hydraulic motor, which can be changed to provide high or low cycles and high or low amplitude as desired.

The connection of a source of hydraulic fluid under pressure to the vibrator with automatic control provided in the hydraulic circuit thereof serves to impart regular vibrations of desired amplitude of between 1,000 and 2,000 vibrations per minute to the frame 48 for rocking this frame on the axis of the shaft 50 relative to the oscillating frame 34. The amplitude varies inversely with the speed of the vibrations, i.e. high vibrations with small amplitude. Inasmuch as the arbor of the cutoff wheel is also supported on the frame 48, the consequent vibrations will be imparted to the wheel at the same time as the oscillations of the latter if oscillating movement be used in addition to the vibrating movement as preferred.

It is important that the axes 32, 50 and 58 lie in a common horizontal plane extending lengthwise of the rocking frame 34. This will provide a long arc of swinging movement and a short are of vibration, generally as indicated diagrammatically in F l0. 19.

The hydraulic cylinders described above may be controlled in any suitable or desired manner to accomplish the operations referred to. A conventional hydraulic circuit, including the controls and cylinders, is not illustrated in detail, but the controls are such as to effect the described operations of the piston portions of the hydraulic cylinders. However, I have illustrated in FIG. 5 a control valve 102 for the oscillating stroke cylinder 36 which moves the frame 34 in a rocking motion about the axis of the shaft 32. The control valve 102 is provided with fingers 104 extending in the path of cams 106 mounted on the oscillating shaft 32 so' as to rock the frame 34. One of the cams 106 will shift the position of the valve 102 so as to energize the cylinder 34 to effect downward movement of the forward end of the frame, and thereafter the other cam I06 actuates the valve 102 to energize the cylinder 36 and to move the forward end of the frame 34 in an upward direction. This is illustrated merely as an example of one method that may be used for controlling the oscillation of the rocking frame 34.

Other controls are provided on an upstanding bracket 107, as indicated generally at 108, for effecting operation of the parts of the machine under control of the operator.

The guard assembly 4 is constructed as an enclosed housing having spaced sideplates 109 closed at the back end of an upright plate member 110 and along the top by flanges on the sideplates 109. The sideplates 109 are provided with slots 112 for passage of the arbor shaft 58 therethrough. Different positions of this arbor shaft 58 are shown with respect to the slot 112 in the diagrammatic illustration thereof in FIG. 7, both to indicate the oscillating movement of the frame 34 carrying the shaft and also the lengthwise shifting movement of the frame to move the cutter wheel 60 into the work. The saw operates between the sideplates 109 and may be shifted to the different positions generally indicated in H6. 7 with respect to the work W, which is fed through the opening 6 of the machine.

Provision is made for supplying water to the wheel during the operation thereof to effect cooling of the wheel. The guard assembly 4 has a water inlet 114 near the upper edge of the assembly through the upstanding plate section 110 and through which water under desired velocity and pressure is supplied.

Extending lengthwise of the upper portion of the guard assembly 4 is a transversely extending plate 116 which closes the bottom of a water channel [18 through the guard assembly substantially in longitudinal alignment with the water inlet 114 at one end of the channel and in position for flow through the channel from the inlet substantially throughout the length of the guard assembly at the top thereof over the wheel 60. This channel 118 extends to a water box in the guard assembly 4 adjacent and substantially over the work area.

The forward end of the water channel 118 is turned downward in an inclined direction beneath a plate 120 in the water box and which plate 120 has a downturned end portion 122 so as to direct the water in a generally downward direction over the work area. The water box is closed along the upright side thereof toward the forward end of the machine by wall structure generally indicated at 124 in FIG. 7, so as to direct the large volume of flow downward from the inclined deflection plate 120 over the work and the opposite sides of the wheel.

At the inner side of the water box a water trap is formed, closed by a top section 126 forming a wall between opposite sides of the water box and extending downward to the top ofa water trap 128 formed by bracket structure secured to the inner faces opposite the sidewalls 109 of the guard assembly 4 with intumed flanges 130 (FIGS. 16-17) extending into positions embraced in close relation at opposite sides ofthe wheel 60, and by the plates 17 on the clamps, at opposite sides ofthe water box.

The lower ends of the water trap brackets 128 are in turn connected with the upper ends of brackets 132 (FIG. 12) extending downwardly therefrom to points below the opening 6. These parts 130 and 132 are shown as connected together by pins 134 for detachable interfitting relation to permit of replacement of the respective parts when desired. The back surfaces of the brackets 128 and 132 may be provided, if desired, with recesses or grooves to accommodate the rotary portions of the wheel mountings so as to allow of forward movement of the wheel to a maximum extent.

The water box is open at the bottom directly over the base 2, which latter forms an enclosed chamber adapted to be kept substantially full of cooling water for maximum radiation of the heat therefrom as it circulates through the base. Additional provisions may be incorporated in the structure for effecting cooling of the water before it is recirculated into the inlet 114.

As shown in FIG. 7, the guard assembly and water box are mounted directly on top of the base 2 and adequate provisions for sealing the outer portions thereof should be provided to prevent leakage of water from these parts. These parts may be secured rigidly together as by bolting, as indicated at 136.

As shown in FIGS. 8 to 10, the base 2 has an opening 138 in the top thereof adapted to receive water from the water box as it flows downward over the opposite sides of the wheel and over the work. Extending beneath the opening 138, and lengthwise of the base, is a plate 140 to direct the flow of water from the opening lengthwise of the base 2 into an enlarged chamber 142 at one end of the base from where it may flow through a suitable portion of the base to effect maximum cooling action thereof. These parts of the base are in open communication and sufficiently large to accommodate and contain the relatively large volume of water which circulates therethrough.

In the operation of the machine, the abrasive cutoff wheel 60 is rotated toward the work W by the driving force of the motor 64 which drives the arbor 58 (FIG. 1). In this view, the work is shown as a square bar moved intermittently through the machine on the roller conveyor 8.

The work is held in place on the conveyor 8 by the clamping action of the fence 12 and cylinders 14 and by the vertically actuated clamping plates 16. These hold the work W during the cutting action after which they are released to permit the work to be shifted to the next cutting position.

As will also be apparent from FIG. 14, the clamping plates 16 and bearing plates 17 on either side ofthe wheel 60 seal off the top of the workpiece to confine the water to the cutting and control the flow in the water box 128, 130.

As the wheel 40 is rotated toward the work, the abrasive structure of the wheel generates friction between the peripheral face of the wheel and the work. This is sufficient to allow the wheel to tear out particles of the material forming the work during the operation of the wheel, and thus effect cutting action ofa kerf through the work. i

This cutting action of the wheel is not along a straight line into the work, but rather a compound motion is effected and imparted to the wheel. First, there is an up-and-down rocking motion of the cutting wheel bodily on the axis ofthe shaft 32. Second, there is a vibrating motion, in addition to the oscillating movement, which is effected by the vibrator 100, and which imparts a small amplitude of movement to the arbor shaft 58 about the axis 50in addition to and may be simultaneously with the oscillating movement about the shaft 32, as diagrammatically illustrated in FIG. 19. These compound movements have been found to effect very rapid cutting of the work, even very hard metals. It is possible to operate the wheel at high peripheral speed under these circumstances, of the order of l2,500 s.f.m.

The vibration is effected automatically by the action of the vibrator 100, acting directly on the frame 48. Vibration speed and amplitude are a function of the variable drive motor and tension of the springs. The amplitude of vibration can be varied by adjustment of the tension on the springs 82 (FIG. 11) and the speed of the vibration drive motor. These springs may be replaced with springs ofa different tension, if desired.

The high-speed cutting operation is further made possible by the cooling action effected in the supply oflarge volume of water at high velocity over the top and down opposite sides of the wheel. This assures adequate cooling of the wheel and of the work. The large volume of water flowing down over opposite faces of the wheel carries off the particles removed during the cutting operation.

The water flows into the base which acts as a settling tank not only by the slowness of flow through the trough but also the confinement in the chambers of the base, generally indicated at 142. This provides a large surface area to effect cooling of the water. The water may be withdrawn from the top of the chambers 142 for introduction at 114 by the action ofa suitable pump.

The wheel is moved back and forth in its cutting operation by the feed cylinder 26 substantially between the positions illustrated in FIG. 7. This shifting movement may be made also to accommodate wheels of different sizes and for wear of the wheels in service. The slot 112 should be of sufficient length to effect the back and forth movement as described.

While the invention has been illustrated and described in one embodiment, it is recognized that variations and changes may be made therein without departing from the invention set forth in the claims.

Iclaim:

1. A cutoff machine having a rotatable saw wheel, an arbor supporting the wheel for turning-movement about an axis at right angles to the plane of the wheel, supporting means for the arbor including oscillating means for swinging movement of the arbor axis in a vertical are, means for imparting a vibrating movement to the wheel in the direction of the vertical are about an axis spaced from the axis of the vertical arc, said vibrating means being separate and spaced from said oscillating means, and separate means for moving the wheel into or out of contact with the work.

2. A cutoff machine according to claim 1, wherein the axes are parallel to each other and are spaced-apart, substantially in a common plane.

3. A cutoff machine according to claim 1, wherein the supporting means comprises an oscillating frame mounted thereon for rocking movement, and said vibrating means comprises a vibrating frame mounted on said oscillating frame, said wheel arbor being supported on said vibrating frame.

4. A cutoff machine according to claim 3, including adjustable means connected with the vibrating frame for yieldably limiting the vibrating movement.

5. A cutoff machine according to claim 3, in which there are provided a bed for supporting the oscillating frame, said moving means being adapted to move the bed lengthwise, and power operated means for effecting rocking movement of the oscillating frame.

6. A cutoff machine according to claim 3, including variable speed drive means for the vibrator providing variable cycles and variable amplitude.

7. A cutoff machine including a base, a bed mounted on the base for longitudinal movement relative thereof, an upstanding guard mounted on the base beside the bed, said guard having an opening therein for receiving work and having a slot in alignment with the opening, an oscillating frame mounted on the bed for swinging movement, an arbor carried by the oscillating frame and extending in said slot, a saw wheel carried by the arbor in the guard, means for vibrating the saw wheel relative to the swinging movement thereof, and means for moving the bed to cause movement of the arbor lengthwise of the slot and thereby move the saw wheel into or out of the work.

8. A cutoff machine according to claim 7, wherein the base has a water reservoir therein, and means for circulating water from said reservoir to a point above the wheel for downward flow to the cutting area.

9. A cutoff machine according to claim 7 including a pair of clamping members mounted on either side of said guard above the opening therein so as to bear against the top surface ofthe work.

10. A cutoff machine according to claim 7 wherein said clamping plates include means for confining liquid supplied above the wheel to the area of work on either side of the wheel.

11. A cutoff machine comprising a base, a bed mounted on the base of longitudinal movement relative thereto, an upstanding guard mounted on the base beside the bed, said guard having an opening therein for receiving work and having a slot in alignment with the opening, a pair of clamping plates mounted on opposite sides of said guard and above the opening so as to bear against the top surface of the work, an oscillating frame mounted on the bed for swinging movement, an arbor carried by the oscillating frame and extending in said slot, a saw wheel carried by the arbor in the guard, and means for moving the bed to cause movement of the arbor lengthwise of the slot and thereby move the saw wheel into or out of the work.

12. A cutofimachine according to claim 11, wherein said base includes a water reservoir and said guard includes a passageway extending along the upper portion thereof, and further comprising a water box in the guard over the work and means for circulating liquid to said water box from the reservoir.

13. A cutoff machine according to claim 12, wherein said clamps include plates mounted thereon to form opposite sides ofsaid water box.

14. A cutoff machine according to claim l3, further comprising a water trap formed at the inner side of said water box, said water trap being formed by a pair of inturned flanges in close relation to said wheel at opposite sides thereof.

15. A cutoff machine comprising a first frame, supporting means mounting said first frame for swinging movement in a vertical are, means for oscillating said first frame, a second frame pivotably mounted on said first frame for movement about an axis substantially parallel to the axis of the vertical arc, means for vibrating said second frame, said vibrating means being separate and spaced from said oscillating means, separate adjustable means for yieldably limiting the vibrating movement of said second frame with respect to said first frame, a saw wheel rotatably mounted on said second frame, and a drive motor opcratively connected to said saw wheel.

16. A cutoff machine according to claim 15, wherein said yieldable limiting means includes upper and lower arm projcetions at one end of said second frame and a rail intermediate the upper and lower arm projections at one end of said first frame, and a cushioning means disposed between said rail and the upper and lower arm portions.

17. A cutoff machine according to claim 15, wherein said supporting means includes a base, a bed mounted on the base for longitudinal movement of said saw wheel into or out of the work.

18. A cutoff machine according to claim 17, including an upstanding guard mounted on the base beside the bed, said guard having an opening therein for receiving work and having a slot in alignment with the opening, said saw wheel being positioned in the guard for lengthwise movement and having an arbor extending in said slot.

19. A cutoff machine according to claim 18, wherein the base has a water reservoir therein, and means for circulating the water from said reservoir to a point above the wheel for downward flow to the cutting area. 

1. A cutoff machine having a rotatable saw wheel, an arbor supporting the wheel for turning movement about an axis at right angles to the plane of the wheel, supporting means for the arbor including oscillating means for swinging movement of the arbor axis in a vertical arc, means for imparting a vibrating movement to the wheel in the direction of the vertical arc about an axis spaced from the axis of the vertical arc, said vibrating means being separate and spaced from said oscillating means, and separate means for moving the wheel into or out of contact with the work.
 2. A cutoff machine according to claim 1, wherein the axes are parallel to each other and are spaced-apart, substantially in a common plane.
 3. A cutoff machine according to claim 1, wherein the supporting means comprises an oscillating frame mounted thereon for rocking movement, and said vibrating means comprises a vibrating frame mounted on said oscillating frame, said wheel arbor being supported on said vibrating frame.
 4. A cutoff machine according to claim 3, including adjustable means connected with the vibrating frame for yieldably limiting the vibrating movement.
 5. A cutoff machine according to claim 3, in which there are provided a bed for supporting the oscillating frame, said moving means being adapted to move the bed lengthwise, and power operated means for effecting rocking movement of the oscillating frame.
 6. A cutoff machine according to claim 3, including variable speed drive means for the vibrator providing variable cycles and variable amplitude.
 7. A cutoff machine including a base, a bed mounted on the base for longitudinal movement relative thereof, an upstanding guard mounted on the base beside the bed, said guard having an opening therein for receiving work and having a slot in alignment with the opening, an oscillating frame mounted on the bed for swinging movement, an arbor carried by the oscillating frame and extending in said slot, a saw wheel carried by the arbor in the guard, means for vibrating the saw wheel relative to the swinging movement thereof, and means for moving the bed to cause movement of the arbor lengthwise of the slot and thereby move the saw wheel into or out of the work.
 8. A cutoff machine according to claim 7, wherein the base has a water reservoir therein, and means for circulating water from said reservoir to a point above the wheel for downward flow to the cutting area.
 9. A cutoff machine according to claim 7 including a pair of clamping members mounted on either side of said guard above the opening therein so as to bear against the top surface of the work.
 10. A cutoff machine according to claim 7 wherein said clamping plates include means for confining liquid supplied above the wheel to the area of work on either side of the wheel.
 11. A cutoff machine comprising a base, a bed mounted on the base of longitudinal movement relative thereto, an upstanding guard mounted on the base beside the bed, said guard having an opening therein for receiving work and having a slot in alignment with the opening, a pair of clamping plates mounted on opposite sides of said guard and above the opening so as to bear against the top surface of the work, an oscillating frame mounted on the bed for swinging movEment, an arbor carried by the oscillating frame and extending in said slot, a saw wheel carried by the arbor in the guard, and means for moving the bed to cause movement of the arbor lengthwise of the slot and thereby move the saw wheel into or out of the work.
 12. A cutoff machine according to claim 11, wherein said base includes a water reservoir and said guard includes a passageway extending along the upper portion thereof, and further comprising a water box in the guard over the work and means for circulating liquid to said water box from the reservoir.
 13. A cutoff machine according to claim 12, wherein said clamps include plates mounted thereon to form opposite sides of said water box.
 14. A cutoff machine according to claim 13, further comprising a water trap formed at the inner side of said water box, said water trap being formed by a pair of inturned flanges in close relation to said wheel at opposite sides thereof.
 15. A cutoff machine comprising a first frame, supporting means mounting said first frame for swinging movement in a vertical arc, means for oscillating said first frame, a second frame pivotably mounted on said first frame for movement about an axis substantially parallel to the axis of the vertical arc, means for vibrating said second frame, said vibrating means being separate and spaced from said oscillating means, separate adjustable means for yieldably limiting the vibrating movement of said second frame with respect to said first frame, a saw wheel rotatably mounted on said second frame, and a drive motor operatively connected to said saw wheel.
 16. A cutoff machine according to claim 15, wherein said yieldable limiting means includes upper and lower arm projections at one end of said second frame and a rail intermediate the upper and lower arm projections at one end of said first frame, and a cushioning means disposed between said rail and the upper and lower arm portions.
 17. A cutoff machine according to claim 15, wherein said supporting means includes a base, a bed mounted on the base for longitudinal movement of said saw wheel into or out of the work.
 18. A cutoff machine according to claim 17, including an upstanding guard mounted on the base beside the bed, said guard having an opening therein for receiving work and having a slot in alignment with the opening, said saw wheel being positioned in the guard for lengthwise movement and having an arbor extending in said slot.
 19. A cutoff machine according to claim 18, wherein the base has a water reservoir therein, and means for circulating the water from said reservoir to a point above the wheel for downward flow to the cutting area. 